SPRINGMVC Freemarker returns global return

I will be useful in the program to some data need to return data from the background to the page. The data that any controller needs to use, so I'm thinking of something that can be returned uniformly. As for how to do in Springmvc I do not know at present, so I trickery with freemarker to deal with.

Define a class, inherit Freemarkerview, override the Exposehelpers method as follows

 Public class extends Freemarkerview {      privatestaticfinal String context_path = "WebRoot";        @Override        protectedvoidthrows  Exception {            model.put (CONTEXT _path, Request.getcontextpath ());                               Super . Exposehelpers (model, request);}        }

This variable of Webroot can be used anywhere on the page. Instead of requiring the modelmap of each controller to return

Springmvc Freemarker returns global return